1. Field of the Invention
The present invention relates generally to fingerprint authentication that can be used for a portable telephone, etc., that has a fingerprint authenticating function, and more particularly to a fingerprint authenticating apparatus, a fingerprint authenticating method, a fingerprint authenticating program, and a portable terminal device that can cope with variation of relative positions of a fingerprint detecting unit and a finger to detect the fingerprint thereof.
2. Description of the Related Art
As portable terminal devices such as portable telephones, etc., those having a fingerprint authentication function for identifying users thereof prevail. As to such fingerprint authentication, Japanese Patent Application Laid-Open Publication No. 2000-270385 discloses an apparatus that includes authentication input means in the main body thereof, and extracts characteristics of a fingerprint image received from the fingerprint input means and checks whether or not the extracted fingerprint characteristics are present in registered fingerprint characteristics.
The fingerprint authentication is executed by checking whether or not inputted fingerprint information is present in the registered fingerprint information. Therefore, when the inputted fingerprint information does not coincide with the registered fingerprint information, the fact that a person is the principal can not be confirmed. For an apparatus configured to, for example, be able to be opened and closed by connecting two (2) housing units with a hinging unit such as a portable telephone, an inputted form of a fingerprint into the fingerprint detecting unit differs between those for the time when a fingerprint is inputted from the housing units that are opened and for the time when the fingerprint is inputted from the housing units that are closed, though a fingerprint detecting unit is installed in a specific position. Therefore, because a detected pattern is varied according to these forms of use, inconvenience that the authentication takes time may be expected when authentication detection rate is lowered. Therefore, the user may feel inconvenience that the user has to pay attention to the direction of his/her finger against the fingerprint detecting unit or the direction in which the finger is placed, etc.
Japanese Patent Application Laid-Open Publication No. 2000-270385 discloses or suggests nothing as to this problem and discloses or suggests no configuration to solve the problem.